6533b82ffe1ef96bd129645b

RESEARCH PRODUCT

Direct Analysis of Phase I Metabolites, Phenol Sulfates, Glucuronides and Glutathione Conjugates of Benzo[a]pyrene in Freshly Isolated, Hypothermically Stored and Cryopreserved Hepatocytes

subject

description

Abstract The complex biotransformation of benzo[a]pyrene (BaP), the prototype of the class of carcinogenic polycyclic aromatic hydrocarbons, can be used as a tool to characterize the capacity of in vitro systems for the biotransformation of xenobiotics. In order to account for the ability of liver parenchymal cells to metabolize BaP, a method was developed for the isolation, separation and quantitation of its phase I metabolites, e.g. tetrahydrotetraols, trans-dihydrodiols, quinones and phenols, as well as its phase II metabolites, e.g. sulfates, glucuronides and glutathione conjugates, employing a combination of extractive and chromatographic steps. Upon incubation of BaP with freshly isolated hepatocytes of untreated rats at least 9 phase I metabolites, one group of phenol sulfates, 8 glucuronides and 7 glutathione conjugates were formed. After hypothermic storage of the cells for 24 h the complete phase I and phase II biotransformation of BaP was well maintained, while cryopreserved hepatocytes exhibit...